
Leqembi
Leqembi (lecanemab or lecanemab-irmb) is FDA approved to treat people with early Alzheimer's disease. This is when they have mild cognitive impairment or mild dementia. Leqembi (lecanemab) is a type of monoclonal antibody that's given as an infusion into a vein. It's given at an infusion center once every 2 weeks. Later on during treatment, there's an option to get the infusions once every 4 weeks. Common side effects include infusion-related reactions and headache. Leqembi (lecanemab) is not a cure for Alzheimer's disease.
What is Leqembi (lecanemab)?
What is Leqembi (lecanemab) used for?
- Early Alzheimer's disease (when there's mild cognitive impairment or mild dementia)
How Leqembi (lecanemab) works
Leqembi (lecanemab) is a type of monoclonal antibody. It finds and attaches to proteins in the brain called amyloid beta (or beta-amyloid). In Alzheimer's disease, these proteins clump together. This forms plaques that can be harmful to your brain cells.
Leqembi (lecanemab) works to lessen the buildup of these plaques in the brain. This might help slow Alzheimer's from getting worse.
Drug facts
| Common Brands | Leqembi |
|---|---|
| Drug Class | Amyloid beta-directed antibody |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | No lower-cost generic available |
| Availability | Prescription only |
More on Leqembi (lecanemab) essentials
Side effects of Leqembi (lecanemab)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
- Infusion-related reaction (26%)
- Bleeding in the brain (14%)
- Swelling or fluid buildup in the brain (13%)
- Headache (11%)
Less Common Side Effects
- Nausea or vomiting
- Rash
- Irregular heart rhythm (atrial fibrillation or AFib)
- Low white blood cell count
Leqembi (lecanemab) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Problems in the brain: headache, confusion, dizziness, vision changes, trouble communicating, weakness, trouble walking, nausea, seizure
- Infusion-related reaction: trouble breathing, dizziness, fever, chills, body aches, joint pain, pounding chest, nausea, vomiting
- Severe allergic reaction: swelling in the face or throat, tightening of the throat, chest tightness, trouble breathing
The following Leqembi (lecanemab) side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions or angioedema—skin rash, itching or hives, swelling of the face, eyes, lips, tongue, arms, or legs, trouble swallowing or breathing
- Headache, worsening confusion, dizziness, change in vision, nausea, seizures
- Infusion reactions—chest pain, shortness of breath or trouble breathing, feeling faint or lightheaded
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Pros and cons of Leqembi (lecanemab)
Pros
- Given once every 2 weeks or every 4 weeks
- Can help slow down Alzheimer's disease from getting worse in people with mild symptoms
- Helps lessen amyloid beta plaques in the brain
- No known interactions with other medications
Cons
- Not a cure for Alzheimer's disease
- Must be given as an IV infusion by a nurse
- Must get MRI scans before and during treatment
- Not studied in people with moderate or severe Alzheimer's disease
Pharmacist tips for Leqembi (lecanemab)
- Make sure to put your appointments for your Leqembi (lecanemab) infusions on your calendar. This helps you stay on track with your treatment. Also put in your scheduled MRI scans. These are important for making sure the medication isn't causing any serious problems. Have a caregiver help you keep track of your appointments.
- If you miss a Leqembi (lecanemab) infusion, call your care team to reschedule it as soon as possible.
- Bring a book or something to do to help pass the time during your Leqembi (lecanemab) infusion. Each infusion takes about 1 hour. But it can sometimes take longer if you have reactions to the infusion and your nurse needs to slow it down.
- During your Leqembi (lecanemab) infusion, tell your nurse if you don't feel well. Let them know if you have any flu-like symptoms, dizziness, nausea, or trouble breathing. These could be signs of infusion-related reactions. Your nurse might slow down the infusion and give you medications to help you feel better.
- If you've had a reaction to the infusion, you might need to take certain medications before the rest of your Leqembi (lecanemab) infusions. These medications can help prevent infusion reactions or make them less severe. Some examples are antihistamines, acetaminophen (Tylenol), and steroids.
- Tell your prescriber if you take medications that help lower the risk of blood clots. This includes aspirin and blood thinners. Your prescriber will check for possible bleeding problems in your brain more often while you're taking Leqembi (lecanemab).
- It's encouraged for you to join a program called the Alzheimer’s Network for Treatment and Diagnostics (ALZ-NET). This program helps researchers learn more about Alzheimer's disease. It also helps them find out more about how treatment for Alzheimer's disease affect you. Ask your prescriber for more information.
Risks and warnings for Leqembi (lecanemab)
Leqembi (lecanemab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Amyloid related imaging abnormalities (ARIA)
- Risk factors: Having two copies of the apolipoprotein E ε4 (ApoE ε4) gene | Taking medications that can raise bleeding risk
Leqembi (lecanemab) can cause a side effect called amyloid related imaging abnormalities (ARIA). They're usually found on MRI scans and look like swelling or bleeding in the brain.
Check with your prescriber about your risk of ARIA with Leqembi (lecanemab). ARIA can also happen to anyone, but the risk seems higher for those with the ApoE ε4 gene. Also let them know about any medications you take or plan to take. Certain medications like aspirin or clopidogrel (Plavix) might raise your risk of bleeding in the brain.
ARIA most commonly happens early in treatment (within the first 14 weeks, or 3.5 months). But it's important to note that it can happen at anytime. It can also happen more than one time during treatment.
Most people with ARIA don't notice any symptoms. That's why you'll need to get an MRI before and during treatment to watch out for it. If you do have symptoms, they usually go away over time. But some can be more serious and life-threatening. Call your care team right away if you have a headache, vision changes, dizziness, nausea, trouble walking, or a seizure.
Infusion-related reactions
Some people can have a reaction from the Leqembi (lecanemab) infusion itself. These reactions can include fever, chills, body aches, and feeling shaky. It can also cause nausea, vomiting, and changes in your blood pressure. Most times, these reactions are mild. But some can be serious. In studies, most reactions happened with the first infusion.
Tell the nurse if you don't feel well, have trouble breathing, or feel your chest pounding during your Leqembi (lecanemab) infusion. The nurse can slow down the infusion or stop it completely. They can give you supportive care to help with symptoms if needed. Your prescriber might give you medications for you to take before your next infusion. This can help lower your chance of having another reaction.
Allergic reactions
Some people have had very serious allergic reactions to Leqembi (lecanemab). They can include severe swelling, trouble breathing, and anaphylaxis. Get medical help right away if you notice hives, swelling in your face or throat, or trouble breathing.
Leqembi (lecanemab) dosage
Typical dosage for Leqembi (lecanemab)
Leqembi (lecanemab) is given as an intravenous (IV) infusion. This means it's injected into a vein. It's given by a healthcare professional at an infusion center.
Your prescriber will calculate the dosage based on body weight.
The typical starting dose is 10 mg/kg of weight given as an IV infusion once every 2 weeks. After a year and a half, you have the option to get infusions once every 2 weeks or once every 4 weeks.
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